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    <title>Document</title>
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<script>
    var num = 10
    var obj = {
        num: 20
    }
    obj.fn = (function (num) {
        this.num = num * 3
        num++
        return function (n) {
            this.num += n
            num++
            console.log(num);
        }
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    var fn = obj.fn
    fn(5)
    obj.fn(10)
    console.log(num, obj.num);
</script>

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